[0001] The present invention concerns improvements in adjustable devices of mechanisms transmitting
the controls from a shedding machine to the heald frames of a loom.
[0002] As known, a shedding machine (or weave machine) is apt to control the heald frames
of a loom by way of linkages, the articulated head of which allows two adjustments:
an adjustment of the head position along the control lever - fixed stroke rocking
lever - of the shedding machine (to adjust the heald frame stroke), and an adjustment
of the head length (to adjust the starting position of the heald frame stroke).
[0003] Different constructions of said articulated head are already known - for example
from CH-A-621.159 - and widely used, but they all have the drawback to comprise a
single locking system for the two adjustments. This makes it necessary to always operate
both adjustments, even when wishing to carry out only one.
[0004] The object of the present invention is to supply an articulated head of the linkage
for the control of the loom heald frames by a shedding machine, allowing to carry
out independently the adjustment both of the heald frame stroke and of the starting
position of said stroke, thereby evidently simplifying the operations involved and
allowing the operators to save considerable time.
[0005] For this purpose, the present invention concerns an articulated head of the control
linkage for the heald frames of looms, operating on the control lever of a shedding
machine to carry out the adjustment both of the heald frame stroke and of the starting
position of said stroke, characterized in that it essentially consists of a stiff
long guide and of a drawer longitudinally sliding therein with precision, the guide
and the drawer being provided with a recess and with wide slots to house transversally
said control lever, and in that, to the drawer there are associated first wedge-shaped
locking means to block the drawer on the control lever and second wedge-shaped locking
means to block the drawer to the guide, screw means being interposed between the guide
and the drawer to adjust the longitudinal position of this latter into said guide,
said first and second wedge-shaped locking means being operated and released one independently
from the other, so as to carry out said two adjustments independently.
[0006] In said articulated head, the first wedge-shaped locking means suitably comprise
a pair of opposed wedges, partially inserted into the slots of the guide and of the
drawer and connected by adjustable screw means, in engagement with inclined transversal
surfaces of a solid part of the drawer and with the side of the control lever of the
shedding machine.
[0007] The second wedge-shaped locking means in turn suitably comprise a wedge interposed
between said guide and said drawer, in engagement with an inclined longitudinal surface
of a solid part of the drawer, and screw means to move said wedge along said inclined
surface.
[0008] According to the invention, said screw means interposed between the guide and the
drawer, to adjust the longitudinal position of this latter into the guide, suitably
comprise a screw which screws into a block fixed to said guide and into a solid part
of said drawer.
[0009] The invention is now described in further detail, with reference to the accompanying
drawings, which illustrate - by mere way of example and without introducing any limitations
- a preferred embodiment thereof, and in which:
Fig. 1 is a diagram showing the transmission of the controls from a shedding machine
to the heald frame of a loom, comprising a linkage with an adjustable articulated
head;
Fig. 2 is a detailed front view of the adjustable articulated head, according to the
invention, forming part of the control linkage in the transmission of fig. 1;
Figs. 3, 4 and 5 show cross-sections of said articulated head, along the lines III-III,
IV-IV and V-V, respectively, of fig. 2.
Fig. 6 shows a longitudinal section of said articulated head, along the line VI-VI
of fig. 2; and
Fig. 7 shows one end of the articulated head of fig. 2.
[0010] With reference to fig. 1, in the operation of a loom, the shedding machine 1 causes
a control lever 2 to oscillate by a fixed angle β. A linkage 3 transmits to the heald
frame 4 the controls of the lever 2, to which it is connected by an adjustable head
5, the eye 6 of which is hinged to the connecting rod 7 of the linkage 3.
[0011] According to the invention, the adjustable head 5 (see figs. 2 to 7) consists of
a stiff long guide 8, ending into the eye 6, and of a drawer 9 longitudinally sliding
with precision into the guide 8. The guide 8 and the drawer 9 are both provided with
an inner transversal wide recess, opening on the sides into two longitudinal opposite
slots, 10 and 11 respectively, to house transversally the control lever 2.
[0012] The drawer 9 comprises a wide solid part 12, with two inclined transversal surfaces
13 in correspondence of its inner end and an inclined longitudinal surface 14 on one
side. The outer end of said solid part 12 carries two threaded holes 15 and 16.
[0013] At the end of the guide 8 opposite to the eye 6 there is applied by screws - after
the drawer 9 has been introduced therein - a block 17, into which is formed a threaded
hole 18 meant to be in alignment with the threaded hole 16 of the solid part 12 of
the drawer 9.
[0014] The adjustable head 5 is completed by first wedge-shaped locking means to block the
drawer 9 on the control lever 2, by second wedge-shaped locking means to block the
drawer 9 to the guide 8, and by screw means 23, interposed between said guide and
said drawer, to adjust the longitudinal position of this latter into the guide.
[0015] The first wedge-shaped locking means comprise a pair of opposed transversal wedges
19, which are partially inserted into the slots 10 and 11 of the guide 8 and of the
drawer 9 so that their inclined side engages with the inclined transversal surfaces
13, and one of their non-inclined sides is apt to engage with the side of the control
lever 2. The wedges 19 are connected together - and thus apt to be drawn close and
apart - by a screw 20, which can be operated externally of the head 5, on its side.
[0016] The second wedge-shaped locking means comprise a longitudinal wedge 21 interposed
between the guide 8 and the drawer 9, an inclined side of which engages with the inclined
longitudinal surface 14 of the solid part 12 of the drawer 9, and a non-inclined side
of which engages with one of the inner sides of the guide 8. A screw 22, inserted
into the threaded hole 15 of the solid part 12 of the drawer 9 - and apt to be operated
externally of the head 5, at its end opposite to the eye 6 - allows to move the wedge
21 longitudinally along said inclined surface 14.
[0017] The screw means interposed between the guide 8 and the drawer 9 - to adjust the longitudinal
position of the drawer, allowing it to be inserted into said guide and be blocked
therein - finally comprise a screw 23, which screws into the hole 18 of the block
17 fixed to the guide 8 and into the hole 16 of the solid part 12 of the drawer 9,
and which can be operated externally of the head 5 at its end opposite to the eye
6, said screw 23 being close and to the side of the screw 22.
[0018] With the aforedescribed head according to the invention, the two adjustments - of
the heald frame stroke and of the starting position of said stroke - can be carried
out in an easy and practical way, one independently from the other.
[0019] In fact, the blocking of the head 5 on the control lever 2 of the shedding machine
is obtained by tightening the screw 20 which draws close the wedges 19 so as to force
them between the side of the control lever 2 and the solid part 12 of the drawer 9,
along the inclined surfaces 13 of said solid part 12. In this way, the lever 2 is
blocked to the drawer 9, onto whose bottom 9A said lever 2 bears with its side opposite
to that engaged by the wedges 19. Since the drawer 9 is blocked to the guide 8 by
the second wedge-shaped locking means, the head 5 remains blocked on the control lever
2 in the selected position.
[0020] If one should wish to change the point of the control lever 2 having to be engaged
by the articulated head 5 - in order to adjust the heald frame stroke - one must simply
loosen the screw 20 and shift the head 5 in respect of the lever 2, thus freed, as
far as the new wanted position, wherein it will be sufficient to tighten again the
screw 20 in order to obtain the locking. This is done without in the least modifying
the distance between the lever 2 and the eye 6 of the head 5 (that is, without affecting
the adjustment of the starting point of the heald frame stroke).
[0021] On the other hand, the blocking of the drawer 9 into the guide 8 is obtained by tightening
the screw 22: this in fact forces the wedge 21 between the inclined surface 14 of
the solid part 12 of the drawer 9 and the inner side of the guide 8, blocking said
drawer to said guide in the reciprocal position set by the degree of tightening of
the screw 23 into the hole 16 of the solid part 12 and into the hole 18 of the block
17 fixed at the end of the guide 8.
[0022] If one should wish to change the length of the articulated head 5 (i.e. the distance
of the control lever 2 from the eye 6 of said head 5) - in order to adjust the starting
point of the heald frame stroke - one must simply loosen the screw 22, to allow the
drawer 9 to freely slide into the guide 8, and then act on the screw 23 to vary the
reciprocal position between drawer and guide, thereby changing in the wanted manner
the distance of the lever 2 from the eye 6 of the head 5, while the lever 2 remains
fixed to the drawer 9 being blocked thereon by the first wedge-shaped locking means
19. The screw 22 is then again tightened to lock together the drawer 9 and the guide
8. This adjustment is obtained without in the least affecting the adjustment of the
length of the heald frame stroke.
[0023] It is understood that other embodiments of the articulated head according to the
invention, differing from the one described and illustrated heretofore, fully fall
within the protection scope thereof.
1. Articulated head of the control linkage for the heald frames of looms, operating on
the control lever (2) of a shedding machine to carry out the adjustment both of the
heald frame stroke and of the starting position of said stroke, characterized in that
it essentially consists of a stiff long guide (8) and of a drawer (9) longitudinally
sliding therein with precision, the guide and the drawer being provided with a recess
and with wide slots (10, 11) to house transversally said control lever (2), and in
that, to the drawer (9) there are associated first wedge-shaped locking means (19)
to block the drawer on the control lever, and second wedge-shaped locking means (21)
to block the drawer to the guide (8), screw means (23) being interposed between the
guide (8) and the drawer (9) to adjust the longitudinal position of this latter into
said guide, said first and second wedge-shaped locking means (19, 21) being operated
and released one independently from the other so as to carry out said two adjustments
independently.
2. Articulated head as in claim 1), wherein said first wedge-shaped locking means comprise
a pair of opposed wedges (19) partially inserted into the slots (10, 11) of the guide
(8) and of the drawer (9) and connected by adjustable screw means (20), in engagement
with inclined transversal surfaces (13) of a solid part (12) of the drawer (9) and
with the side of the control lever (2) of the shedding machine.
3. Articulated head as in claim 1), wherein said second wedge-shaped locking means comprise
a wedge (21) interposed between said guide (8) and said drawer (9), in engagement,
with an inclined longitudinal surface (14) of a solid part (12) of the drawer (9),
and screw means (22) to move said wedge (21) along said inclined surface (14).
4. Articulated head as in claim 1), wherein said screw means interposed between the guide
(8) and the drawer (9) to adjust the longitudinal position of this latter into the
guide, comprise a screw (23) which screws into a block (17) fixed to said guide (8)
and into a solid part (12) of said drawer (9).